only occasional user newbie q on how pgp works

[dave]

I don't often use pgp and just "press the button" to get a pgp file ie
I can use it but don't understand much. I have a question or two
perhaps someone can explain for me?

When first use pgp I run it and enter a pass phrase. This pass phrase
is used then to generate two keys (pub and private). I see how this
idea works for encrypting and decrypting. However - subsequently when
I enter the pass phrase, is that "just" to allow me access to my
private key?

If so then the pass phrase is used to (this is a question):-
-generate a pub/private key pair
-allow later access to the private key
(?)

The keyrings store just public keys?

To protect my pgp usage I need to store (off-disc), my private key(s)
and pass-phrases?

If the private leys are lost/destroyed - can my pass-phrase alone
regenerate my private key (I suspect I have just asked a really stupid
question)

Thanks for any enlightenment.

[David E. Ross]

Post by dave
I don't often use pgp and just "press the button" to get a pgp file ie
I can use it but don't understand much. I have a question or two
perhaps someone can explain for me?
When first use pgp I run it and enter a pass phrase. This pass phrase
is used then to generate two keys (pub and private). I see how this
idea works for encrypting and decrypting. However - subsequently when
I enter the pass phrase, is that "just" to allow me access to my
private key?
If so then the pass phrase is used to (this is a question):-
-generate a pub/private key pair
-allow later access to the private key
(?)
The keyrings store just public keys?
To protect my pgp usage I need to store (off-disc), my private key(s)
and pass-phrases?
If the private leys are lost/destroyed - can my pass-phrase alone
regenerate my private key (I suspect I have just asked a really stupid
question)
Thanks for any enlightenment.

Your private key is stored with your public key in your keyring. Unlike
your public key, however, your private key is encrypted before storing.
Your passphrase is used both to encrypt your private key (thus is
needed when you create your key-pair) and to decrypt your private key
(thus is needed whenever you use your private key). This is why you can
actually change your passphrase without having to create a new key-pair.

You should never store your passphase anyplace except in your head.

Your keyring actually consists of two files, one with public keys and
one with private keys. (Yes, you might have created more than one
key-pair.) Some people do indeed put the file with the private keys on
removable media, which they must attach to their computer when they use
PGP to either decrypt or sign (both of which require a private key).

No, your passphrase cannot be used to recreate your private key. It was
not really used to create your private key in the first place. It was
used only to encrypt your private key before storing it into your keyring.

If you lose your private key, you are in trouble. See my
<http://www.rossde.com/PGP/pgp_keyserv.html#noremove>, paying special
attention to the text just after the third bullet ("But what can you
do...").

Also see my <http://www.rossde.com/PGP/pgp_encrypt.html#basic>.

[Unruh]

Post by dave
I don't often use pgp and just "press the button" to get a pgp file ie
I can use it but don't understand much. I have a question or two
perhaps someone can explain for me?
When first use pgp I run it and enter a pass phrase. This pass phrase
is used then to generate two keys (pub and private). I see how this

Nope. Those two keys are generated from random data ( keyboard presses,
etc) The passphrase is to protect your private key stored on the disk.

Post by dave
idea works for encrypting and decrypting. However - subsequently when
I enter the pass phrase, is that "just" to allow me access to my
private key?

Yes.

Post by dave
If so then the pass phrase is used to (this is a question):-
-generate a pub/private key pair

No

Post by dave
-allow later access to the private key

Yes.

Post by dave
(?)

No.

Post by dave
The keyrings store just public keys?
To protect my pgp usage I need to store (off-disc), my private key(s)
and pass-phrases?
If the private leys are lost/destroyed - can my pass-phrase alone
regenerate my private key (I suspect I have just asked a really stupid
question)
Thanks for any enlightenment.